UTEP researchers found that nanoplastics and PFAS chemicals significantly alter proteins essential for human development, such as those in breast milk and myoglobin, potentially leading to developmental disorders and other health problems. These findings underscore the urgent need for safer alternative materials and provide a basis for future environmental policy.
A UTEP study finds that both nanoplastics and permanent chemicals modify key proteins in breast milk and infant formula.
Researchers at the University of Texas at El Paso have made significant advances in the study of nanoplastics and per- and polyfluoroalkyl substances (PFAS), also known as forever chemicals. Their research shows how these compounds can alter the structure and function of biomolecules. In particular, the team found that these substances can alter proteins in breast milk and infant formula, potentially leading to developmental problems later in life.
Nanoplastics and forever chemicals are man-made compounds that are ubiquitous in the environment; a series of recent studies have linked them to numerous negative health effects. While nanoplastics are primarily created as a result of the breakdown of larger plastic materials, such as water bottles and food packaging, forever chemicals are found in a variety of products, including cookware and clothing.
The UTEP research team focused on the compounds’ impact on three proteins critical to human development and function: beta-lactoglobulin, alpha-lactalbumin, and myoglobin. Their findings, which provide atomic-level insight into the harmful effects of nanoplastics and PFAS on human health, are described in two recent papers in the Journal of the American Chemical Society And ACS Applied Materials and Interfaces.
Mahesh Narayan, Ph.D., professor and chair of the Biochemistry Division in UTEP’s Department of Chemistry and Biochemistry. Credit: The University of Texas at El Paso
“By understanding the molecular mechanisms of how nanoplastics and forever chemicals disrupt cellular functions, scientists can develop safer alternatives to these materials,” said Mahesh Narayan, Ph.D., a professor, fellow of the Royal Society of Chemistry and chair of the Biochemistry Division in UTEP’s Department of Chemistry and Biochemistry, who oversaw the two studies. “The insights gained from this research have far-reaching implications.”
Narayan said their research showed in particular that nanoplastics and PFAS completely “dissolved” a region of proteins known as the alpha helix, converting it into structures called beta sheets.
“We didn’t expect them all to have such a similar impact on the alpha helix,” Narayan said. “It was a complete fluke.” The team found that this change also occurs in amyloid proteins, which can cause neurodegeneration and neurotoxic outcomes if the synthetic chemicals reach the brain.
The key additional findings from the studies are described below.
Milk protein: beta-lactoglobulin (BLG)
BLG is a protein found in the milk of sheep and cows and is often used as an ingredient in infant formula. The protein binds to retinol (vitamin A) and fatty acids and is crucial for vision and brain development in infants.
The research team found that the binding efficiency of BLG to retinol and fatty acids decreases with exposure to nanoplastics and PFAS. This decrease, modeled by Lela Vukovic, Ph.D., an associate professor in the Department of Chemistry and Biochemistry, could lead to significant developmental problems in newborn babies, the team said.
In addition, the team observed for the first time that PFAS bind to the milk protein, making it a carrier for these substances.
The research team includes (top row, L-R): Mahesh Narayan, Ph.D., professor and chair of the Biochemistry Department in UTEP’s Department of Chemistry and Biochemistry; Randhal Ramirez Orozco, doctoral student in computer science; Sophia Borrego, sophomore in biomedical sciences; Samantha Arce, sophomore in biomedical sciences; Daisy Wilson, doctoral student in environmental science and engineering; (bottom row, L-R) Ummy Habiba Sweety, doctoral student in environmental science and engineering; and Jyotish Kumar, doctoral student in the Department of Chemistry and Biochemistry. Lela Vukovic, Ph.D. (not pictured), associate professor in the Department of Chemistry and Biochemistry, was also involved in the research. Credit: The University of Texas at El Paso
Human breast milk: alpha-lactalbumin
Alpha-lactalbumin is found in breast milk, plays a role in the synthesis of lactose and is ingested by babies to help meet nutritional needs. UTEP researchers found that nanoplastics and PFAS disrupt the structure of alpha-lactalbumin protein, potentially compromising lactose formation. The team said the disruption could lead to developmental defects in newborn babies, such as weakened immune systems and reduced mineral absorption.
Oxygen storage: Myoglobin
Myoglobin, found in the blood and muscle tissue of most mammals, is crucial for storing oxygen. The UTEP research team found that nanoplastics and PFAS compromise the functionality of the myoglobin protein, disrupting its ability to store oxygen. This disruption can lead to health problems such as shortness of breath and anemia.
Additional experiments by the team showed that exposure to nanoplastics impairs the worms’ locomotion, with effects similar to those of paraquat, a herbicide linked to Parkinson’s disease.
“This work has the potential to have a significant impact on public health and environmental policy, and highlights the critical role of scientific research in addressing global challenges,” said Robert Kirken, Ph.D., dean of the College of Science. “I am proud of the groundbreaking research conducted by Dr. Narayan, Dr. Vukovic and their teams. Their innovative approach to understanding how these man-made materials disrupt biomolecular functions is a prime example of the transformative work UTEP researchers are doing regularly.”
Narayan and his research team plan to continue their research and investigate the effects of other types of plastic and PFAS compounds.
References: “An atomic and molecular insight into how PFOA reduces α-helicality, compromises substrate binding, and creates binding pockets in a model globular protein” by Anju Yadav, Lela Vuković, and Mahesh Narayan, April 24, 2024, Journal of the American Chemical Society.
DOI: 10.1021/jacs.4c02934
“Interfacial Interactions between Nanoplastics and Biological Systems: Towards an Atomic and Molecular Understanding of Plastic-Driven Biological Dyshomeostasis” by Afroz Karim, Anju Yadav, Ummy Habiba Sweety, Jyotish Kumar, Sofia A. Delgado, Jose A. Hernandez, Jason C. White, Lela Vukovic, and Mahesh Narayan, May 9, 2024, ACS Applied Materials & Interfaces.
DOI: 10.1021/acsami.4c03008